Mechanism for truing and dressing grinding wheels



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Feb. 1521925. 1,526,496

I F. J. HQHNHORST ET AL. I

MECHANISM FOR TRUING AND DRESSING GRINDING WHEELS Filed y 1; 1924 2 heets-Sheet 1 F. J. HQHNHORST ET AL MECHANISM FOR TRUING AND DRESSING GRINDING WHEELS Filed May 51. 1924' Patented Feb. 17, 1925.

ii i 1 1,526,496

UNITED STATES PATENT OFFICE.

FERDINAND J. HOHNHOlR-S'I AND FERDINAND J'. KROEGER, OF COVINGTON, KEN- TUCKY.

MECHANISM FOR TR-UING AND DRESSING GRINDING WHEELS.

Application filed May 31, 1924. Serial No. 717,015.

To all whom it may concern:

Be it known that we, FERDINAND J. HOHN- HORST and FERDINAND J. KROEGER, citizens of the United States, residing at Govington, in the county of Kenton and State of Kentucky, have ointly invented certain new and useful Improvements in Mechanism for Truing and Dressing Grinding Wheels, of which the following is a specification;

Our invention relates to mechanism for truing and dressing grinding wheels, such as emery wheels employed in machinery for grinding or polishing the surfaces of metal in precision grinding, and is employable for truing and dressing the grinding wheel without removing the grinding wheel from the grinding or polishing machine.

It is the object of our invention to provide a plurality of rotary abrading parts having non-parallel axes of rotation arranged to contact the grinding surface of a grinding wheel in such manner that the abrading actions of the respective abrading parts upon the grinding surface of the grinding wheel will be counter to each other; further, to provide a plurality of rotary abrading parts coacting with the grinding surface of the same grinding wheel and presented toward said grinding surface at angles with relation to each other; fur ther, to provide means whereby the angular relation of the abrading parts with relation to each other is adjusted; further, to provide a plurality of rotary abrading wheels supported proximate to each other by bearings at the outsides of said collective abrading wheels; further. to provide means whereby to relatively position said bearings with relation to each other for attachment and removal of the abradin'g wheels; further, to provide rotary abrading wheels which are tilted toward each other in a plane located within an angle of ninety degrees from that plane parallel to the axis of rotation of the grinding wheel in which said axis and the points of'contact of said rotary abrading wheels and said grinding wheel are located; further, to provide means for collectively adjusting said rotary abrading parts in angular relation with the axis of rotation of the grinding wheel; and, further, to provide rotary abrading parts in such respective relations which are normally quiescent, with the rotary motion imparted to the rotary abrading parts by contact thereof with the rotating grinding Wheel.

The invention will be further readily understood from the following description and claims, and from the drawings, in which latter:

Fig. 1 is a plan view of our improved device applied to an exemplified grinding machine, partly broken away.

Fig. 2 is a cross-section of the same, taken on the line 22 of Fig. 1, and partly broken away.

Fig. 3 is a diagrammatic representation of the relation of the abrading wheels and a grinding wheel viewed from the top.

Fig. 4 is a side elevation of an exemplification of our improved device, partly broken away.

Fig. 5 is a plan view of the same, partly in section on the line 5-5 of Fig. 4.

Fig. 6 is a cross-section of the same, taken on the line 66 of Fig. 5.

Fig. 7 is a plan view of our improved de vice. in which the rotary abrading parts are shown as dressing disks; and,

Fig. 8 is a side elevation of the same, partly broken away.

lVe have exemplified our invention as employed in connection with a so-called grinding or polishing machine employing a rotary grinding wheel 11 for effecting grinding or polishing.

The work to be ground or polished, which may for instance be a shaft, is ar anged to he placed between suitable centers 12, 13, of which 12 may exemplify a head center, arranged to be rotated by suitable driving means, as a pulley 14, a usual quill 15 in which the head-center is supported in usual manner being journaled in a bearing 16 of a head-stock 17. slidable laterally on guideways 18, 19, of a table 20.

The tail-center 13 is mounted in a suitable sleeve 21, movable axially in a bearing 22, in usual manner, the bearing being on atail-stock 23 laterally adjustable on the guideways 18, 19, of the table 20.

The table is exemplified as pivotally mounted by a pivot 25 on a saddle 26, which has lateral reciprocating motion imparted thereto by power means, in usual manner, as by a pinion 27, suitably driven, meshing with a rack 28 extending lengthwise of the saddle. The saddle is slidable laterally on guideways 29, 30, on the frame 31 of the machine.

The grinding wheel 11 is suitably fixed to a shaft 34: journaled in bearings 35 of a I the medium of the ing withthe T-slot 39 in the frame, and

the nuts clamping the slide to the frame. The shaft is rotatable in suitable manner, as by a belt passing about suitable pulleys 4-0, e1, fixed to the shaft.

y In the exemplification, the work located between the centers may be caused to 'reciprocate axially in planes parallel to the axis of rotation of the shaft of the grinding wheel for grinding or polishing straight work, or the table maybe adjusted to an angle with relation to said parallelism, ef-

fected, for instance, by rotation of the handle 42 according to the reading on the gage 43.

Vi e have in the present exemplification illustrated a reciprocating table on which to mount the work, the grinding wheel having a stationary position, although the re lation of the parts. may be reversed, the work being stationarily positioned and the grinding wheel having reciprocations im parted to it. We have instanced the abrading aarts as acting on the grinding wheel in the absence of work between the centers. The grinding machine may be of any desirable construction.

The rotary abrading parts are exemplified as abrading wheels 45, 145. These rotary abrading'wheels are in their preferred form, illustrated in Figs. 1 to G'inclusive, of a texture much harder than the grinding wheel and of much smaller diameter than the diameter of the grinding wheel on which they operate. The rotation imparted to the grinding wheel is instanced as in the di rection-of the arrow (4, while the rotations imparted to the abrading wheels through grinding wheel are instanced as in the directions of the arrows 2'), 0. p r

In the-modificationshown in Figs. 7 and 8 we have'illustrated the rotary abrading parts as roughing wheels 45, 145, used primarily for rough-truing or rough-dress- "ing the grinding wheel, and comprising respectively,- for example, disks 46 provided with peripheral teeth'47, which may be of hardened metal, other parts of the device shown in FigsJF and 8 being'exem'plified the same as similar parts" described particularly with reference to'Figs. l to 6 inclusive, and designated bysimilar reference numerals. v

The grinding wheel during operation becomes impregnated with particles of dirt or metal' from the work being operated on,

and becomes comparatively glossy and thereby loses its grmding effect, its granular structure also becoming dull at the grinding face, thereby reducing its grinding or polishing properties.

By means of our invention, the particles of dirt and metal are removed from the grinding surface of the grinding wheel by coacting rotary abrading parts which act counter to each other or crossingly with relation to each other upon the grinding surface of the grinding wheel, whereby to clear the recesses and pores in the grinding surface, as by having the respective abrading parts coact in different directions for drawing and wiping the particles of dirt and metal out of said recesses and pores, by successive actions thereon by the respective rotary abrading parts, to dislodge the dirt and metal and refuse therefrom, effected, for instance, by the opposite positions and opposite formations of the rotary abrading parts. The rotary abrading parts further coact in different directions with the grinding surface for sharpening the particles or grains in said surface.

The'grinding or polishing effect of the grinding wheel is determined by the fineness or coarseness of its grinding surface, and we have provided means whereby to regulate such fineness or coarseness in order to dress the grinding wheel according v to the work which it is to perform.

lation between said axes of rotation when a coarser grinding surface is desired and causing said axes of rotation to be more nearly parallel when a finer grindingsurface is desired.

The more said axes of rotation are out of parallel with each other, the greater will be the swirling action of the abrading surface upon the grinding surface, in order to clean the peripheral interstices or pores of the grinding wheel by brushing or drawing out the dirt or particles of metal which may be lodged in said interstices or pores, the swirling action of the respective rotary abrading parts upon the grinding surface being in opposite directions so that the swirling action of one of said rotary abrading parts is to draw the dirt or particles of metal out ofthe interstices or pores in one direction, whereas the other rotary abrading part acts upon said dirt or particles in the other direction, so as to insure that said particles of dirt and metal are dislodged from said interstices or pores, whereby the cleaning and abrading effect is increased and the time consumed in the operation is decreased, and, furthermore, these oppositely swirling movements aid in producing exceptionally sharp conditions of the particles or grains 'for'enhancing the grinding properties of the abrading parts act to produce true cylindrical forin in the grinding wheel.

The abrading wheels are preferably tilted with relation to each other so as to present oppositely inclined paths oi rotation to the grinding wheel, and oppositely inclined paths of wiping movement upon the grinding surface of the grinding wheel. The exemplified tilting may be said to be the resultant eii ect of tilting the abrading wheels in both a horizontal plane and in a vertical plane, producing a tilting in an intermediate direction, or about midway between said planes, for instance, as indicated in Fig. 3.

The 'abrading wheels preferably have their points of closest approach at points in angles of the outer peripheries of said. wheels located between the plane in which the aXis of rotation of the grinding wheel and the points of contact between the abrading wheels and said. grinding wheel are 10- rated and a plane at right angles thereto intersecting the middle portions of the abrading wheels, which angle is an angle within ninety degrees, the points of closest approach being preferably approximately in the middle of said angle for most etlicient truing, cleaning and dressing results.

W e also prefer to mount the rotary abrading parts so that they may be adjusted about an axis located in or between said rotary abrading parts and in said grinding wheel, so as to present said rotary abrading parts at an additional angle to the rotary grinding wheel. We have instanced this accomplished by mounting the rotary abrading parts collectively on a shank, and adjusting the shank rotatively, for adjusting the positions of the rotary abrading parts with relation to the grinding wheel, means being also provided to adjust the shank axially toward and from the grinding wheel.

The nearer the collective abrading wheels are adjusted into parallelism with the grinding wheel, the finer will be the finish imparted to the grinding wheel, for producing a polishing effect upon the work, and the greater the angle to which the abrading wheels are adjusted with relation to the grinding wheel, preferably not exceeding 30 degrees, the coarser will be the finish imparted to the grinding wheel for cutting 67* tects upon the work. i

0 shall describe the mounting of the abrading wheel 45, the mounting of the abrading wheel 14-5 being similar thereto, but having the parts disposed in opposite directions, the parts being designated by similar reference numerals, but increased to the series 100.

Thus the abrading wheel 45 is exemplified as secured to a mandrel 51, provided. with a flange 52, and iS shown clamped to said mandrel by means of a nut 53, a washer 5 for instance of leather, being located between the grinding wheel and the flange, and washers 55, 56, the former of leather. being located between the abrading wheel and the nut, the nut clamping said abrading wheel and washers between the flange and the nut, and being threaded over the threaded end 57 of said mandrel.

A hearing-housing 58 has bearings 59, (50, therein for the mandrel, the bearings being shown as combined radial and end-thrust ball-bearings. The ballhearing 59 comprises an inner race 61 and an outer race (32. The hall-bearing 60 is provided with an inner race 63 and an outer race (34. The inner races are shown secured to the mandrel, the inner race 61 contacting a reduced shoulder 65 on the flange 52 at one end thereof, and being contacted at its other end by a bushing 66 about which the inner race 63 is received against an annular shoulder 67, a nut 68 on the outer threaded end 69 of the mandrel clamping the inner race 61, the bushing 66 and the inner race 63 between the shoulder 65 and the nut.

The outer race 62 is received against an annular shoulder 71 in the bearing-housing at one end of said race, a collar 72 separating said outer races 62, 64, and a plug 73, received in the outer threaded socket 74 ot the bearing-housing, clamping the outer races and the collar therebetween between the annular shoulder 71 and said plug. This plug forms a closing cap for the outer end of the bearing-housing, there being a compressible washer 75 located between the inner end of the bearing-housing and the rotatable abrading wheel.

The threaded portions of the mandrel are preferably such as to be counter to the di rection of rotation of the respective abrading wheels, and they are instanccd as righthand threads on the mandrel 51, and as letthand threads on the mandrel 15].

The respective bearing-housings 58, 158, are on arms 77, 177, on a shank 78, forming a fork-like support for the rotary abrading parts. The space between the arms is pref erably adjustable for adjusting the angle 1 between the rotary abrading parts, and preferably also for convenience of atta hmentand removal of the rotary ahrading parts. e have instanced this adjustment as accoi'nplished by providing the arm 77 with wings 80, and providing the arm 177 with wings 180, and providing the shank with a wing 81, a bolt 82 being received through coincident holes in the wings. the parts being clamped together by a nut 83.

The arms respectively have extensions 85, 185, in which bolts 86, 186. are threaded, the inner ends of the bolts having connections with the shank, as by ball and socket joints 87, 187. Nuts 88, 188, are arranged to clamp the bolts in adjusted positions,

The turning of either bolt moves the cor responding arm inwardly or outwardly according to the direction in which the boltis turned, for adjusting the abrading wheel thereon with relation to the shank.

, The abrading wheels are also preferably adjusted about an axis substantially parallel with the axis of the shank, for adjust ing the paths of the rotary abrading parts at additional angles to the path of the rotary grinding wheel. This latter adjustment moves one of the abrading wheels upwardly and the other abrading wheel down.- wardly about the axis of their supporting shank, and presents the abrading wheels to the grinding wheel in such manner as to enhance the. swirling effects of the respective abrading wheels in cleaning and removing particles of dust and metal from the interstices and-pores in the grinding surface of the grinding wheel, and in sharpening the particles and grains of the grinding wheel.

The means employed for fixing the abrading meansv to the grinding or polishing machine and pcrn'iitting said last-named adjustment, are exemplified as follows:

The table of the grinding or polishing machine .is, in the present instance, provided with a guide 101 and a rail 102. A clamp 103 is provided with a jaw 10 i co-act-ing with the guide and a clamping means comprising a jaw 106 having an inclined face 107 on the body of the clamp and a clampplate 108, the inclined face and the clampplate being arranged to clamp upon the rail 102.

A stem 111 is located in a bearing! 112 of the clamp. An adjusting nut 115 and a lock nut 1.16 are received over the threaded end 117 of said stem. Said stem is provided with a flattened head 119, a fork 120 of a handle 121 being received about said head and articulated therewith by means of a pin 122.

The head 119 is received through, a slot in a cap 126. The inner end of the fork 120 is provided with cams 129 and shoulders 130, arranged to bear against the cap, and to cause clamping movement between said cap and the clamp-plate 10S atone side of the rail 102 and the inclined face 107 at the other side of said rail, causing clamping of the jaw upon said rail.

The body of the clamp is provided with a bearing 135, shown as a clamp-bearing, in which the shank 7 8 is received, and in which said shank may be adjusted axially and rotatively, for adjusting the relation of the rotary abrading parts tothe grinding wheel as hereinbefore explained. When such adjustments have been made, the clamp-bearing is clampedabout the shank by means of bolts 136, received through holes of a cheek 138 and threaded in threaded holes of a cheek 140, the cheeksbeing located at the respective sides of the split 1 11 in said clamp-bearing, which is thereby constituted a split-bearing.

The respective arms 77, 177, are provided with flanged guards 44, 11 1, protectingly received about the rotary abrading wheel.

Our improved device provides ready and convenient means for obtaining quick and effective truing, dressing, cleaning and sharpening of the grinding wheel in novel manner, and provides means which act with a cross-wiping motion in paths which cross each other upon the surface of the grinding wheel for cleaning, truing, dressing and sharpening the grinding surfaces.

Having thus fully described our invention, what we claim as new, and desire to secure by Letters Patent, is:

1. In mechanism for truing and dressing grinding wheels, the combination of a support, a plurality of rotary abradingparts thereon arranged to operate on the same grinding wheel, and means for positioning said rotary abrading parts with their axes of rotation in non-parallel relation.

2. In mechanism fortruing and dressing grinding wheels, the combination of a support, a plurality of rotary abrading parts thereon arranged to operate on the same grinding wheel, means for positioning said rotary abrading parts with their axes of rotation in non-parallelrelation, and means for adjusting the angle between said axes of rotation.

3. In mechanism for truing and dressing grinding wheels, the combination of a sup port, a plurality of rotary abrading parts thereon arranged to operate on the same grinding wheel, means for positioning said rotary abrading parts so as to have nonparallel axes of rotation, and means for collectively adjusting said axes of rotation about a common axis.

1. In mechanism for truing and dressing grinding wheels, the combination of a support, a plurality of rotary abrading part-s thereon arranged to operate on the same grinding wheel and having axes of rotation, and means for positioning said rotary abrading parts on a plurality of axes respectively substantially perpendicular to said axes of rotation and substantially perpendicular to each other.-

5. In mechanism for truing and dressing grinding wheels, the combination with a grinding wheel, of a plurality of rotary abrading wheels arranged to contact therewith relatively angularly positioned and having their closest approach at points in the outer peripheries of said abrading wheels between their points of contact with said grinding wheel and an angle of ninety degrees thereto in said abrading wheels.

6. In mechanism for truing and dressing grinding wheels, the combination with agrinding wheel, of a plurality of rotary abrading wheels in planes which are nonparallel to each other, said abrading wheels having their closest approach at a point in the angle between that plane of the axis of rotation of the grinding wheel in which the axes of rotation of the abrading wheels are located and a plane at right angles thereto intersecting said last-named axes of rotation.

7. In mechanism for truing and dressing grinding wheels, the combination with a grinding wheel, of a plurality of normally quiescent rotary abrading wheels arranged to contact said grinding wheel and located in planes tilted toward each other in the angle between that plane parallel to the axis of rotation of the grinding wheel in which said axis and the points out contact between said wheels are located and a plane at right angles thereto in which the axes of rotation of the abrading wheels are located, and arranged whereby said rotary abrading wheels rotate in angular relation on contact with said rotating grinding wheel.

8. In mechanism for truing and dressing grinding wheels, the combination of a plurality of normally quiescent rotary abrading parts arranged to operate on the same grinding wheel, and means for positioning said rotary abrading parts on nonparallel axes of rotation, and arranged whereby said rotary abrading parts rotate in angular relation on contact with a rotating grinding wheel.

9. In mechanism for truing and dressing grinding wheels, the combination of a plurality of normally quiescent rotary abrading parts arranged to operate on the same grinding wheel, and means for positioning said rotary abrading parts at angles with relation to each other and to said grinding wheel, whereby on contact between said rotary abrading parts and said grinding wheel said rotary abrading parts are caused to rotate, with a differential wiping action in opposite directions on said grinding wheel.

10. In mechanism for truing and dressing grinding wheels, the combination with a grinding wheel, of a support, a plurality of rotary abrading wheels thereon arranged to operate on the said grinding wheel, and means for positioning said rotary abrading wheels on said support with their axes of rotation arranged at an angle with relation to each other and to said grinding wheel.

11. In mechanism for truing and dressing grinding wheels, the combination with a grinding wheel, of a plurality of rotary abrading wheels arranged to operate on said grinding wheel, and means for positioning said rotary abrading wheels on said support with their axes of rotation arranged at an angle with relation to each other and with their axes of rotation combinedly at a different angle to the axis of rotation 01? the grinding wheel.

12. In mechanism for truing and dressing grinding wheels, the combination with a grinding wheel, of a plurality of rotary abrading wheels arranged to operate on said grinding wheel, and means for positioning said rotary ahrading wheels with their axes of rotation arranged at an angle with relation toeach other in a given plane and at angles with relation to the axis of rotation of said grinding wheel in a different plane.

13. In mechanism :for truing and dressing grinding wheels, the combination with a grinding wheel, of a plurality oi. rotary abrading wheels, means for pireitioning said rotary abrading wheels with their axes of rotation arranged at an angle with relation to each other in a given plane, and means for adjusting the distance and angle between the proximate ahrading portions of said rotary ahrading wheels.

1%. In mechanism for truing and dressing grinding wheels, the combination of rotary mandrels in endwise relation to each other, abrading wheels on proximate ends of said mandrels, and bearings for said mandrels at the outside faces of said abrading wheels, said bearings positioned at an angle with relation to each other.

15. In mechanism for truing and dressing grinding wheels, the combination OI rotary mandrels in endwise relation to each other, abrading wheels on the proximate ends or said mandrels, bearings for said ahrading wheels at the outside faces of said abrading wheels, said bearings positioned at an angle with relation to each other, and a shank on which said bearings are mounted.

16. In mechanism for truing and dressing grinding wheels, the combination of rotary mandrels in endwise relation to each other, abrading wheels on the proximate ends of said mandrels, bearings for said mandrels at the outside faces of said abrading wheels, said bearings positioned at an angle with relation to each other, a shank on which said bearings are mounted, and means for positioning said bearings about an axis substantially parallel with said shank.

17 In mechanism for truing and dressing grinding wheels, the combination of rotary mandrels in endwise relation to each other, abrading wheels on the proximate ends of said mandrels, bearings for said mandrels at the outside faces of said abrading wheels, said bearings positioned at an angle with relation to each other, a shank on which said bearings are mounted, a bearing for said shank, and means for axially and rotatively adjusting said shank in said lastnamed bearing.

18. In mechanism for truing and dressing grinding wheels, the combination of a pair of arms, a bearing on each of said arms, a

mandrel in each of said bearings, and means.

'mandrels between said bearings arranged for-receiving abrading wheels, and means for fixing'th'e approach relation between said arms, whereby separation between said arms permits insertion and removal of abrading wheels onthe proximate ends of said inandrels.

20. In mechanism for truing and dressing grinding wheels, thefcoinbination of a support, arms pivoted thereon provided with ends swinging with relation to said support, a bearing on each of said swinging ends, a mandrel in each of said bearings, the proximate ends of said mandrels between said bearings arranged for receiving abrading wheels, means for adjusting the distance relations between said swinging ends, and means for securing said arms in adjusted relations.

21; In mechanism for truing and dressing grinding wheels,-the combination of a support, a pair of arms provided with wings, means for pivoting said wings'to said: support, a bearing at one endof each of said arms, a mandrel in eachof said'beari'ngs, the proximate ends of said mandrel's arranged for receiving abrading wheels, and adjusting means between the other ends of said arms and said support where-by to ad'- jnst the angular relation between said bearings.

22. In mechanism for truing and dressing grinding wheels, the combination of a support, a pair of arms, said support and said respective arms provided with complemental wings pivoted together for swinging relation of said ams on said support, a bearing in the swinging end of each of said arms, a mandrel in each of said bearings, the proximate ends of said mandrels between said bearings arranged for receiving abrading' wheels, means for adjusting said arms on said support, and a clamp for clamping together said wings for'fixedj relation of said arms on said support. i

In testimony whereof, we have hereunto signed our names in the presence'of two subscribing witnesses.

- FERDINAND J, HQHNHORST.

FERDINAND J.;KROEGER.

Witnesses:

DELMA WERNSING,

PAUL I; Co-NNOLLY. 

